I think I heard some of his Avengers theme (probably the only Marvel theme/cue I can hum/whistle from memory) in Civil War but I could be mistaken
I miss recognizable themes/cues in these Marvel movies like John Williams, Jerry Goldsmith and James Horner used to do in their work but I guess that kind of scoring is corny these days.

James Horner passed away last year and Jerry Goldsmith passed away 12 years ago.

Probably a good call to make this one movie instead of two as people begin to tire over superhero movies. They had a good 10 year run - time for a bit of a break

I don't think they're taking a break from the avengers. From what I got in the article, two Avengers are coming in 2018 and 2019. I still think Infinity War will lead into the untitled movie, they probably don't want to give away too much about it right now.

“You know that we’re onto something within the studio when we hit upon an idea or we see a piece of concept art and all of us in the room go, ‘This is cool,'” Feige said in a video released Friday evening by Marvel Studios via Twitter. “And in ‘Avengers: Infinity War, the Avengers will meet the Guardians of the Galaxy.” Along with Feige’s words, a piece of concept art showing Rocket and Thor fighting side by side is seen in the video.

Probably a good call to make this one movie instead of two as people begin to tire over superhero movies. They had a good 10 year run - time for a bit of a break

Marvel’s “Avengers: Infinity War” and its untitled sequel are shooting back to back, no longer being filmed simultaneously.

Marvel Studios President Kevin Feige told Collider, “We’re doing them one right after another. … It became too complicated to cross-board them like that, and we found ourselves — again, something would always pay the price. We wanted to be able to focus and shoot one movie and then focus and shoot another movie.”